Paleontology

Polyptychodon

Polyptychodon was a 23 foot long pliosaur which lived around North America, South America, and Europe during the middle Cretaceous Period 100-90 million years ago. The name Polyptychodon means “many-folded tooth” and refers to the ribbed surface on the teeth’s… Read More ›

Asteracanthus

Asteracanthus was a 6 foot long hybodont shark which lived from the middle Jurassic Period to the middle Cretaceous Period 165-100 million years ago. Unlike most prehistoric sharks which are known only from teeth, Asteracanthus is also known from some… Read More ›

Cretalamna

Cretalamna, meaning “chalk shark”, was a 10 foot long shark which lived from the middle Cretaceous Period to the Eocene Epoch of the Paleogene Period 105-46 million years ago. Cretalamna was one of the first so-called “modern” sharks to appear…. Read More ›

Cretodus

Cretodus, meaning “chalk tooth”, was a 22 foot long shark which lived throughout the world during the middle to late Cretaceous Period 100-85 million years ago. Cretodus was one of the first “modern” sharks to appear on earth during the… Read More ›

Todiltia

Todiltia schoewei was a small prehistoric saltwater fish which lived in North America during the middle Jurassic Period 165 million years ago. Fossils of this fish have been found in Colorado and New Mexico within the Todilto Limestone Member of… Read More ›

Occithrissops

Occithrissops willsoni was an 8 inch (20 cm) long saltwater fish which lived within the Sundance Sea during the middle Jurassic Period 165 million years ago. During the middle of the Jurassic Period, much of the center of North America… Read More ›

Plesiosuchus

Plesiosuchus was a 20 foot long marine crocodylomorph which lived in the tropical sea which once covered Europe during the late Jurassic Period 155-150 million years ago. In the 1860s, fragmentary fossils were discovered in Dorset, England by a local… Read More ›

Xenacanthus

Xenacanthus, meaning “strange spine”, was a 3 foot long shark-like freshwater fish which lived in North America, South America, Europe, and Asia from the second half of the Carboniferous Period to the end of the Permian Period, approximately 323-251 million… Read More ›